topic Re: Revit formula with multiple conditions - How to write in Revit Architecture Forum

Revit formula with multiple conditions - How to write

Jessicas — Thu, 23 Mar 2017 21:03:00 GMT

HI,

I have a family i'm creating and there's a nested item that needs to be visible under certain circumstances.

Its a U-Shaped family, the sides are visibly controlled by yes/no parameters

There's a centre support that needs to be visible if the length gets to 8' or above.

So this is what I the conditions need to be...

Centre support visible if Length_Main > 7'11"

but if the Left side is visible the necessary length would be 7'11 + 1'4"

if the Right side is visible length would also be 7'11 + 1'4"

if Both sides are visible length would be 7'11" + 2'8"

does anyone know how this would be written. I'm definitely not good with writing the formulas.

Thanks in advance if anyone can show me how the formula would look.

Re: Revit formula with multiple conditions - How to write

ToanDN — Thu, 23 Mar 2017 21:05:14 GMT

Please share the family file.

Re: Revit formula with multiple conditions - How to write

Alfredo_Medina — Thu, 23 Mar 2017 22:20:35 GMT

You need to build a formula that checks for those things in order, from left to right, like this:

first, check if Left is visible and Right is not.
If that is true, do this,
if not
check if Right is visible and Left is not,
if that is true, do this,
if not,
check if both Left and Right are visible
if that is true, do this,
if not,
use a default or base length.

That sequence, translated to a formula, is like this:

Re: Revit formula with multiple conditions - How to write

ToanDN — Thu, 23 Mar 2017 22:45:59 GMT

My shot at it. See if I am missing any conditions.

Re: Revit formula with multiple conditions - How to write

Jessicas — Fri, 24 Mar 2017 12:29:13 GMT

Sorry I was able to post this right at the end of my work day.

Re: Revit formula with multiple conditions - How to write

Jessicas — Fri, 24 Mar 2017 18:17:01 GMT

Can anyone help with this? I've tried quite a few times to get something but i always get errors.

Re: Revit formula with multiple conditions - How to write

ToanDN — Fri, 24 Mar 2017 18:20:35 GMT

Have you tried the formula provided by @Alfredo_Medina and the other one by myself?

Re: Revit formula with multiple conditions - How to write

Jessicas — Fri, 24 Mar 2017 18:24:28 GMT

I tried Alfredo's it seems more towards what i think i need. I tried so many things with it and couldnt get anything to work.

Yours.... honestly i have to idea whats going on 😮 really truely i suck at formula stuff

I attached the family in an earlier reply maybe it will help if people see the actual family set up.

Re: Revit formula with multiple conditions - How to write

ToanDN — Fri, 24 Mar 2017 18:38:33 GMT

We use different approaches to reach the same goal. @Alfredo_Medina created one complex formula that does it all where as I decided to break it apart. I showed screenshots of multiple conditions so you could see how the formula works. It's up to you which one you select.

Re: Revit formula with multiple conditions - How to write

Jessicas — Fri, 24 Mar 2017 18:40:27 GMT

ok. Well I've had to move on so once I get back to that family I'll try your version out and see if i can get it to work.

Re: Revit formula with multiple conditions - How to write

ToanDN — Fri, 24 Mar 2017 19:21:49 GMT

Here is my attempt at your family. Obviously my brain is not as good as @Alfredo_Medina so I needed to add a few more parameters in order to make it work. His original proposal should work if you can digest it.